Relay



R. E. HELLMUND.

RELAY.

APPLICATION FILED SEPT. 2s. 19!].

1,371,560, Patented Mar. 15, 1921.

INVENTOR Irudo/f E. Hel/mund. Fl; 4. BY

; AT TO NEY WITNESSES: 011M 5 62 UNITED STATES PATENT OFFICE.

VANIA.

ASSIGNOB TO WESTING- GOIK'IPANY. A COREORATION OF PENNSYL- RELAY.

Specification of Letters Patent.

Patented Mar. 15, 1921.

Application filed September 28, 1817. Seriai No. 183,894.

1'1; all w/iom may concern:

it known that i. RUnoLr E. HELL- subject of the Emperor of Germany, 1 residentof Swissvalc, in county of voltage holding coil when no current verses or more phases of the circuit. .inother object of my invention is to provide two parallel-connected switches for so ontrolling the circuit of a low-voltage holding coil that it will be positively deenerupon a failure of voltage on any or .ihases of the circuit.

irrther object of my invention is to a device of the above indicated tcr that shall be simple and inc pensive to construct and effective in its operation.

in the accompanying .rawings Figure 1 a diagrammatic view of an electrical circuit embodying my invention; Fig. 2 is a dc"'l front elevational view of the torque shown in Fig. 1:, Fig. 8 is detail elevational view of a modified form of the torque motor shown in Fig. l. and Fig. i a view tel-zen along the line I l IV of Fil 3 A i olyphase induction motor '1 is supplied wth current through conductors 9., 3 and 4 of an electrical circuit. A circuit interrupand a switch 6 are connected in series with the conductors 2, 3 and l, and the circuit interrupter 5 is provided with a novoltage or low-voltage holding coil 7 for the purpose of opening the interrupter 5 when the voltage fails on one or more phases of the circuit supplying energy to the mo tor l.

One terminal of the holding coil 7 is connected to the conductor 4: and its other ter minal is connected to the contact member 8 of a switch 9 and to the contact member 10 of a switch 11. The switch 9 comprises a movable bridging contact member 12 and two resiliently mounted contact members 8 and 13. The movable bridging contact member 9 is so mounted on the movable ans for insuring the deenergization of a member of the switch 6 that it engages the resiliently mounted contact members 8 and i when the switch 6 is opened. Two sta-' tionary members is: are provided for so engaging the contact members 8 and 13 that. when the bridging contact member 12 is moved downwardly, it will disengage the same after it has moved a predetermined distance. The contact member 13 is connected to the conductor 8 of the circuit and to the stationary contact member 15 of the switch 11. Y

The switch 11 comprises the stationary contact members 10 and 15, a movable bridging contact member 16, a spring 17 for biasing the member 1-3 to its open position and a torque motor 18 for moving same to its closed position. The motor 18 is operatively connected to series transformers 19 that are associated with the conductors 2, and l of the circuit. The motor 18 may as constructed along the lines of an induction motor and it is adapted to maintain the corn tactmember 16 in engagement with its stationary contact members 10 and 15 wlie ii current traverses conductors 2, 3 and 4. However. when no current traverses one or more of the phases, the motor 18 will act as a single-phase motor. and, since its r tor is stationary, it will lose its torque and permit the spring 17 to open the switch 11.

hen the circuit interrupter closed. and low voltage obtains across the conductors 3 and e. the holding coil 7 will be over" come by a spring 26 to permit the interrupter 5 to be opened. However, when the switch 6 is closed. the circuit through the trip coil 7 is opened at the switch 9. but, if cur rent traverses all of the conductors 2, 3 and 4 of the circuit. the motor 18 will immediately close the switch 11. Thus, when one of the conductors 2, 3 and 4 is interrupted. the switch 11 will open to deenergize the holding coil 7 and permit the spring 26 to open the interrupter 5.

My invention is particularly adaptable to polyphase induction-motor circuits in which the converter action of the induction motor maintains voltage across all of its phases even when the current traversing one the phases is interrupted. In other words. it is adapted to prevent the failure of operation of the low-voltage coil when volt age is induced in the circuit by the motor.

If it is desired to connect the motor 18 ill) directly in circuit with the conductors 2, 3 and 4 without the use of the transformers l9,it may be constructed as shown in 2, in which the conductors 2, 3 and 4: constitute the windings oi the stator 24 and in which the rotor 20 is constructed in accordance with the usual construction of squirrel is, the castings are adapted to be received in properly displaced openings in the stator of the motor to constitute conductors and end connections therefor and also terminals to which the line conductors may be directly connected to thus preclude the useof the transformers 19. An ordinary squirrel-cage rotor may be used.

I do not limit my'invention tothe particular structures illustrated, as various modifications may be made without departing from the spirit and scope'ot the inven tion asset forth in the appended claims.

I claim as my invention:

1. In a polyphase electric circuit, the coin hination with a switch, 'a circuit interrupter. and a low-voltage coil therefor. of means dependent upon the closure of the switch for opening the circuit of the coil. and means tor closing the circuit of the coil when current traverses each phase of the circuit.

2. In a polyphase electric circuit, the con1 bination with a switch, a circuit interrupter and a low-voltage coil therefor, of two parallel-connected switches for the low-voltage coil circuit, and means for causing one of the switches to be automatically opened when the current traversing one of the phases of the circuit is interruptcd.-

3. In a polyphase electric circuit, the combination with main switch, a circuit interrupter and a low-Voltage holding coil therefor, of two parallel-connectedswitches for the circuit of the holding coil, means for opening one of the switches when the main switch is closed and means for closing the other switch only when current traverses all phases of the circuit.

4. In a polyphase electric circuit, the combination with means for closing the circuit, and a low-voltage coil for effecting opening of the circuit, of two parallel-connected auxiliary switches for the low-voltage coil, means for opening one of the switches when the main circuit is closed, and means for closing the other switch only when current traverses all phases of the electriccircuit.

5. In an electric circuit, the combination with means for closing the circuit and a lowvoltage holding coil for controlling the opening oi? the circuit, of means dependent upon the closing of the circuit for disconnecting the holding coil from the circuit,

and means for connecting the holding coil to.

the circuit only when current traverses the same. p

6. In a p'olyphase electric circuit, the combination with means for closing the circuit and a holding coil controlling the opening of the circuit, of means dependent upon the closing of the circuit for disconnecting the holding coil from the circuit, and an induction motor tor maintaining the circuit of the holding coil closed only when current traverses all phases of the circuit.

7. In an electric circuit, the combination with means for closing the circuit and a holding coil for controlling the opening of the circuit, of means dependent upon the closing of the ircuit for disconnecting the holding coil, and means for connecting the holding coil only when current traverses the circuit.

S. In an electric circuit, the combination with a main switch, a circuit interrupter and a low-voltage holding coil therefor, of two parallel-connected switches for the cir-v cuit of the holding coil. and means for opening one of said switches when the main switch is closed.

9. In a polyphase electric circuit, the combination with a main switch, a circuit interrupter and a low-voltage holding coil there for. of an auxiliary switch actuated by the main switch for opening the circuit of the holding coil when the main switch is closed.

a second auxiliary switch in the circuit of the holdingcoil, and a current relay for openingthe second auxiliary switch when no current traverses one phase of the circuit.

10. In a polyphase electric circuit, the combination with a circuit interrupter and a low-voltage holding coil therefor, of two parallel-connected switches for the circuit be the holding coil. and an induction motor for closing one or said switches whencurrent traverses all phases of the circuit;

In testimony whereof, I have hereunto sub szcrihed my name this 11th day of Sept, 1.91

nnnotr i-inLLMUND. 

